At the poles, (over Antarctica) the winds blow in a circular pattern and create polar vortices. Water droplets present in the atmosphere form ice crystals inside these vortices. CFCs get collected on the surfaces of these ice crystals and destroy the ozone. This has resulted information of a large area of thinned ozone layer, commonly called as the ozone hole over Antarctica.
Excessive UV exposure increases risk of various skin cancers, cataracts and other eye diseases, as well as accelerated skin ageing. It may also adversely affect people's ability to resist infectious diseases. High doses of UV-B causes inflammation of cornea, called snow blindness cataract, etc. Such exposure may permanently damage the cornea.